Scale squeezes were performed on thirteen wells in the Duri Field, Sumatra. At the time the squeezes were completed, seven were designed to be ‘Acid Squeezes’ and six were designed to be ‘Neutral Squeezes.’ In the course of preparing for the scale squeezes, produced waters were collected and analyzed. In addition, scale inhibitor evaluations, and inhibitor compatibility studies were completed.
Simulated squeezes were done in the laboratory to predict field performance. The methodologies and results of the background work are reported. In addition, the relative effectiveness of the two sets of squeezes is discussed. The inhibitor flowback concentrations atler the squeezes, in all cases, can be explained using speciation chemistry and the amorphous and crystalline phase solubilities of the inhibitor used. The wells squeezed with a more acidic inhibitor have more predictable and uniform inhibitor return concentration curves than the wells squeezed with a more neutral scale inhibitor.